Theme X: Glycosides

Glycosides. Definitions, Classification and origin, Examples.

The glycosides are products of the secondary metabolism of plants by the condensation of a sugar with other organic molecules, in which the linkage alpha or beta is made with the hemiacetal hydroxyl. The sugar fraction is called carbohydrate and the other one aglycone or genina.

The pharmacological activity is due to the aglycone, while the sugar is inactive but needed to maintain the overall function of the glycoside since it allows its solubility and absorption.

These compounds are readily hydrolyzed by a proteolytic catalysis only in the linkages alpha and beta. In laboratory environment this hydrolysis is obtained by digestion with dilute acids but in natural state is catalyzed by enzymes that are specific to the type of link genina-sugar, and are named according to the type of glucoside.

Classification and origin of the glycosides

Examples of glycosides

Saponins

Carbohydrates

Glycosides. Definitions, Classification and origin, Examples.